I have a 99 XJ Limited, automatic. I drove it this morning and this afternoon, with no problems starting or running. I went to go out again about an hour and a half after getting home, and my XJ won't start. All the accessories/lights/radio work fine, so the battery is not dead. I can turn the key like I'm starting it up and the engine just keeps turning over and over without cranking up. I tried giving it some gas as I tried to start it up, and while I had my foot on the gas, I was able to keep it running. But as soon as I let up off the gas, it cut off.

I haven't looked at anything under the hood, but wanted to know if anyone had any ideas on what it might be. I'm still learning about cars in general so I didn't even know where to start beyond checking if the battery is dead or not. I've done a bit of searching online and here, could it be a bad starter? Or a problem with the computer? Thanks for any help you all can give!

 

see if you can get it to run long enough to check the fuel pressure... also when was the last time you did a tune up? cap, rotor, plugs, and wires? mine was doing this and turned out to be a bad fuel pump http://www.youtube.com/watch?v=http:...?v=H9BY7EYqIFY

 

x2 it sounds like a fuel problem. is the check engine light on at all? and if it was the starter, u would be able to tell. when starters go bad, they draw more amps or power from the battery and that in turn will put more stress on the battery.

 

well if you were able to keep it running with the pedal down then its not your starter. if the engine is cranking over then the starter works.

this is a tough thing to crack without seeing and experiencing firsthand what its doing.

it could be a number of things,

fuel pump, low fuel pressure
spark plugs wires
throttle position sensor
air intake sensor

i wish i could be of more help

 

Nothing's been done as far as a tune up in awhile, but I don't think it's needed anything done. Just from searching around on the internet, I've ruled out an idle air control valve issue. Since it has not stalled out at all while I've been driving it, and this is the first time it's given me any trouble, it doesn't seem very likely. And based on what you guys have said, it doesn't seem like it's a starter problem.

The problem seems really similar to what was going on in that video. Everything sounds completely normal, my jeep's not shaking or acting up besides not actually starting without the help of me pushing the gas pedal. If it starts to die off, I can give it some more gas and it'll stay running as long as my foot's on the gas.

The check engine light isn't on, and hasn't come on anytime recently.

Seems like it's either something with the computer or a sensor. I'm going to try it again tomorrow, if it's the same deal as tonight I'm going to disconnect the battery to reset the computer and see if that does anything.

 

My best guess is try checking your fuel pump. This is out of topic but I remember when my first car was not starting and the only way it started was spraying some starter fluid on the throttle body and then I found out it was my Fuel Pump. Best of luck

 

Mine did the same thing. It was a sensor. Very elusive....

 

my bet is on the throttle position sensor! also when was the last time you changed your fuel filter?

 

I tried to start it up this morning, just to see if it'd work. It started up on the first try on its own. It sounded like it was struggling a little bit but it cranked on up. I didn't drive it just in case, I didn't want to get stranded in it today.

I just went out again to try it. The first time it acted like it did last night, kept turning over without fully cranking up. I tried again, and my battery completely went out, but that ended up just being a loose connection. Fixed that. Tried it again, got it cranked up but it was shaking some and just sounding not good. The RPM's fluctuated a lot in the few seconds I did have it on. I turned it off, I don't know how long it would have run if I had left it on.

It's starting to sound more like a fuel pump issue. I have a friend who had a problem with a fuel pump and it sounds pretty similar to what's going on with my jeep.

No idea when the fuel filter was last replaced. I've been the main driver of it for the past year or so, but before that my dad had it so I don't know all the details of what's been done on it. But if something needed to be done as part of a routine maintenance, whether every X number of miles or after a certain number of miles is reached, it would have been taken care of.

Are there any guidelines for when to change a fuel filter?

 

i have a 99 also and i only have a sock on the pump i can find no inline filter will look tomorrow if i dont downpour

 

I am having the same exact problem. Nice thing bout Jeeps is that everyone has the same problems! Just wanted to get subscribed to this thread. Rock on

 

seems like there all breaking the same parts round the same time lol

 

I got my jeep to start up last week, a little roughly, but it stayed running. I drove it to a mechanic in town. They told me the throttle body was dirty and a tune up was long overdue. The work they did was cleaned that up, and replaced the spark plugs, plug wires, distributor cap and rotor button. They told me I'd be getting better gas mileage now. I picked my jeep up today and it seems to be running well.

 

Glad you got it sorted out and thanks for posting how you got it fixed.

I do wonder what else is due for maintance, i.e. oil change, coolant check/change, transmission fluid check/change, differentials fluid change, transfer case fluid change, brakes and brake fluid flush. All these can be done pretty easily by anyone that knows the pointy end from the round end of a wrench. If you need help on any of those you know where to ask.